Carburetor



March 22, 1932. N. E. GASTON CARBURETOR Filed March 27, 1950 2 Sheets-Sheet 1 March 22, 1932. N. E.'GASTON CARBURETOR 2 Sheets-Sheet Filed March 27, 1930 gwuentoz aaion Patented Mar. 22, 1932 UNITED? STA-res NATHAN E. GASTON, OF GULFPORT, MISSISSIPPI CARBURETOR Application filed March 27, 1930. Serial No. 439,445.

This invention relates to carburetors for internal combustion engines, and hasfor one of its objects to provide a device of this-char-. acter which shall embody a fuel well, a floating or adjustable main aspirating or jet tube having its intake end immersed in the fuel and its discharge end arranged above the level of the fuel, and means for adjusting the tube so as to increase the height of its discharge end with respect to the level of the fuel as the speed of the engine increases and to decrease the height of its discharge end with respect to the level of the fuel as the speed ofthe engine decreases, to the end that the same proportion of air and fuel Wlll be supplied to the engine at all speeds thereof.

The invention has for a further object to provide a carburetor of the character stated wherein the throttle valve thereof shall constitute a part of the means for adjusting the aspirating or jet tube, to the end that the height of the discharge end of the tube w th respect to the level of the fuel will be increased as the throttle valve is moved in the direction of its opened position and decreased as the throttle valve is moved in the direction of its closed position.

The invention has for a further object to provide a carburetor of the character stated 3 wherein the connection between the aspirating or jet tube and the throttle valve shall be such as to permit an initial movement of the throttle valve from its closed position to be effected wthout any change in the position of the tube, to the end that a rich mixture will be momentarily delivered to the engine so as to effect the rapid acceleration thereof;

The invention has for a further object to provide a carburetor of the character stated wherein the connection between the aspirating or jet tube and the throttle valve shall be such that the engine suction, when the engine reaches its highest speed at any opened position of the throttle valve will raise the aspirating or jet tube to a higher position than it occupied immediately after the movement of the throttle valve into such position, to the. end that the same proportion of air and fuel will be supplied to the engine at all speeds thereof. 1 I

The invention has for a further object to provide a carburetor of the characted stated wherein the connection between the aspirating or jet tube and the throttle valve shall, be such as to permit an initial movement of the throttle valve from its opened position to be effected without any change in the position of the tube, to the end that the mixw ture will not become richer momentarily on deceleration. I r

The invention has for a further object to provide a carburetor of the character stated wherein the connection between the aspirating or jet tube and the throttle valve shall be adjustable so as to permit the extent of the adjustment of the tube by any movement imparted to the throttle valve to be regulated and controlled. The invention has for a'still further ob ject to provide a carburetor of the character stated which shall embody a floating or adjustable idling aspirating or jet tube ad justable automatically by engine suctionto deliver to the engine at all idling speeds thereof-the same proportion of air and fuel.

The invention is hereinafter fully 'described and claimed and illustrated in the ac companying drawings, wherein Figure 1 is a view partly in vertical section and partly inside elevation of a carburetor constructed in accordance with my invention; Figure 2 is a sectional view taken on a plane extending vertically and centrally through the carburetor; i

Figure 3 is a sectional view taken on the horizontal plane indicated by the line 33 of Figure 2;

Figure 4: is a fragmentary sectional view so taken on the vertical plane indicated by the line 4-4 of Figure 1, and

Figure 5 is a fragmentary sectional view taken on the horizontal plane indicated by the line 55 of Figure 4. The carburetor comprises a body 1 which bypreference is of cylindrical formation and is provided with an air inlet opening 2 and a fuel mixture outlet opening 3. The opening 2is located in a side and near the lower end 109 of the body 1, and the opening 3 is located in the upper end of the body. The body 1 is provided at its upper end with a flange 4 to permit the carburetor to be secured to the intake manifold of an engine. An intake tube 5, which extends radially from the body 1, communicates at its inner end with the opening 2. A choke valve 6 of the butterfly type is arranged within the tube 5 and is carried by a shaft 7. The tube 5 is provided with an opening 8 to permit the connection therewith of a ventilator tube for the crank case of the engine. 7

The body 1 is extended downwardly and reduced to provide a fuel well 9 having a lower chamber 10 and an upper chamber 11. A float chamber 12 is carried by the fuel well 9 and communicates with the chamber 10 by way of a passage 13. The float chamber 12, which may be of any well known or appropriate construction, is shown as comprising an inlet 14, a needle valve 15, a float 16, and balance levers 17 The lower end of the chamber 10 is closed by a removable plug 18. The upper end of the chamber 11 communicates with the atmosphere by way of a passage 19, and arranged in the outer end of the passage is an air cleaning means which may consist of a screen 20 or the like.

A wall 21 which separates the fuel well 9 into the chambers 10 and 11, is provided with a central opening 22 for the reception of the main aspirating or jet tube 23. The tube 23 is vertically adjustable, and in any adjusted position thereof its lower or intake end is immersed in the fuel in the well 9 and its upper or discharge end is located above the level of the fuel, the fuel level being indicated by the dotted line 24. The passage of the tube 23 is restricted, as at 25, at a point adjacent its upper or discharge end, and the tube is provided between said restriction and discharge end with lateral air intake ports 26. A piston 27 provided with openings 28, is secured to the lowerend of the tube 23 and is arranged in the chamber 10 to provide a dashpot which functions to retard the movements of the tube.

A combining tube 29 extends upwardly from the upper end of the main aspirating or jet tube 23 and has its lower end arranged in surrounding relation to the aspirating or et tube at a point above the air inlet ports 26. The combining tube 29 is provided in its lower end with air inlet ports 30, and the lower end thereof is tapered downwardly to increase the velocity of the air as it enters the tube. The upper end of the combining tube 29 is slidably arranged in a nozzle 31 which is arranged axially within a Venturi choke or tube 32 which is fixed to and within the body 1 between the air inlet opening 2 and the fuel mixture outlet opening 3. The nozzle tube 31 is secured to and supported in the Venturi choke or tube 32 by ar1ns 33, and it extends above and below the throat of the venturi. A jacket 34, which surrounds the upper end portion of the aspirating or jet tube 23 and the lower portion of the combining tube 29, is secured at its lower and upper ends to the tubes, and its lateral wall is arranged in spaced re lation to the tubes. The jacket 34 has its lower end portion arranged in the fuel well chamber 11 and has its upper portion arranged in the body 1, and is provided in its upper end with air inlet ports 35 which communicate with the air chamber 36 of the body 1. The jacket 34 surrounds the air inlet ports 26 and cuts off all communication between said ports and the fuel well chamber 11. The upper end of this chamber may be closed by any suitable means as for instance, a bushing 37 which surrounds the acket 34 and is secured to the upper end of the chamber, as at 38. The air chamber 36 constitutes that portion of the body 1 located below the Venturi choke or tube 32, and that portion of the body located above this pipe constitutes a mixing chamber which is designated 39.

A throttle valve 40 is mounted in the mixing chamber 39 upon a shaft 41, and the latter is provided outwardly beyond the body 1 with a crank 42 which is secured thereto at a point between its ends. The arm 42a of the crank 42 is adapted to be connected to the hand and foot throttle levers of an automobile, and the arm 42b of the crank is connected to the aspirating or jet tube 23 and combining tube 29 in order that they may be raised by and the result of the movement of the throttle valve 40 in the direction of its opened position and lowered by and as the result of themovement of the throttle valve in the direction of its closed position, to the end that the height of the discharge end of the aspirating or jet tube with respect to the fuel level maybe varied to supply the same proportion of air and fuel to the engine at all speeds thereof. This connection established through the medium of means which comprises a vertical rod which is slidably mounted in bearings 44 carried by the air inlet tube 5 and is connected to the combining tube 29 by a horizontal arm 45. The urm 45 is provided at one end with a sleeve 46 which surrounds the rod 43 and is secured thereto by a set screw 47. The arm 45 extends through the air inlet opening 2, and is provided at its inner end with a fork 48 which surrounds the combining tube 29 and is connected thereto by the upper end of the jacket 34 and a collar 49 secured to the tube. A link 50 which extends from the upper end of the rod 43 to a point above the crank arm 42?). is connected to this crank arm by a coil spring 51 which surrounds the link at a point above the crank arm.

The lower end of the spring 51 is provided with a hook 52 which engages in a slot 53 formed in and extending longitudinally of deliver fuel to the engine.

the crank arm 42?). The upper end of the spring 51 is provided with an eye 54 which surrounds the link between nuts55 threadcdly engaged with the link andv adjustable longitudinally thereon. The spring 51 es tablishes a yielding connection between the aspirating or jet tube 23 and the throttle Valve40, and such connection permits initial 23 with respect to the fuel level '24, to the end that a lean mixture will be momentarily delivered to the engine to permit it to be decelerated rapidly. The nuts 55,. due to their adjustable connection with the link 50, permit the aspirating orjet tube 23 to be adjusted vertically with respect to the throttle valve 40 so as to regulate'and control the extent of the adjustment of the discharge end of the tube downwardly withrespect to the fuel level 24 during any phase of the closing movement of the throttle valve that may be imparted thereto after its initial movement, whereby to regulate the fuel mixture at the lowest engine speed. at which the tube will The link 50 is pivoted at its lower end, as at 56, to the upper 'end of the rod 43, for adjustment toward and away from the throttle valve shaft 41-so as to permit the distance through whichthe aspirating or jet tube 23 will be raised and lowered during each phase of the movement of the throttle valve 40 after the initial opening or closing movement thereof, and thuspermit the leanness of the fuel mixture to be regulated for higher engine speeds. The means by which the link 50 may be adjusted comprises a guide 57 through which the link slidably passes and which is connected to the crank arm for sliding adjustment toward and away from the throttle valve shaft 41. The guide 57 is adjustable through the medium of a screw' 58 which is threadedly engaged with a lug 59 extending outwardly fromthe free end of the crank arm 42?). The guide 57 is locked in its adjusted position by a nut 60 engaged with the screw 58 and contacting with the lug 59. The screw 58 is swivelly connected,

as at 61, to the guide 57, and a portion of the guide is arranged'in the slot 52 of the crank arm 42?; inorder to hold the guide against turning movement during the adjustment thereof.

It will be understood from the foregoing" description, taken in connection with the acmovement of the tube.

companying drawings, that the discharge end of the aspirating o'r jet tube 23 is lowered with respect to the fuel level 24 as the speed of the engine decreases in response to a closing movement imparted to the throttle valve 40, that the discharge end of the tube is raised with respect to the fuel level as the speed of the engine increases in response to an opening movement imparted to the throttle valve, and that due to these adjustments of the discharge end of the tube, the same proportion of air and fuel will be supplied to the engine at all speeds thereof.

This automatic proportioning of the air and fuel results from the shortening of the column of fuel to be lifted by engine suction as the speed and suction of the engine decreases and from the lengthening of the columnof the fuel to be lifted by engine suction as the speed and suction ofthe engine increases, the column of fuel being shortened by the downward movement of the aspirating or jet tube 23 and lengthened by the upward Air flows from the air chamber 36 into the jacket 34 by way of the ports 35 and flows from the jacket into the aspirating or jet tube 23 by way of the ports 26. The air enters the aspirating or jet tube 23 immediately above the restriction 25 thereof, and the air and fuel flow from this tube into the combining tube 29, from the combining tube into the guide tube 31, and from the guide tube into the mixing chamber 39. The air entering the carburetor by way of the inlet opening 2 passes through the Venturi choke or tube 32 around thetube 31 and mixes with the air and fuel in the chamber 39 and this mixture flows into the intake manifold of the engine.

62a so as to take care of the displacement of the fuel from the latter chamber during the adjustment of the aspirating or jet tube 23 which tube is, as stated, balanced in its movements by the dashpot consisting of the at its lower end by a removable plug 63 and at its upper end by the lug 64 formed on the body. The chamber 62 is divided by a par tition'65 into a lower compartment 62a and into an upper compartment 625, the lower compartment comprising a fuel well and the upper compartment a mixing chamber.

The passage 13 from the float chamber 12 communicates directly with the fuel well 62a,

and this well is in communication with the chamber 10 by way of opening 66 and with the chamber 11 by way of opening 67 so as to supply the well 9 with fuel. The fuel well 62a is in communication at its upper end The chamber' 11 IS in communication with a chamber I Que with the air passage 19 by way of a passage i 68 so as to permit a common level of the fuel in this well and the well 9. The mixing chamber 62?) is in communication near its lower end with the air chamber 86 by Way of an opening 69 and near its upper end with the throttle valve seat by way of an opening 70. The idling aspiratingor jet tube 71 is slidably mounted in the mixing chamber 62?) and has its lower or intake end arranged in the fuel well 62a and immersed in the fuel the upper discharge end of the tube being ar-- ranged close to the opening 7 O. The aspirating or jet tube 71 passes through an opening 72 in the partition and is provided near its upper end with a piston 73 which contacts with the inner surface of the chamber 62 and cooperates with the partition to guide the tube in its movements. The passage through the aspirating or jet tube 71 is restricted near its intake end, as at 74. The jet tube is provided above its restricted portion 7 4 with air intake ports 7 5 which communicate with the mixing chamber 62?). A spring 76 mounted on the aspirating or jet tube 71 between the partition 65 and a collar 77 secured to the tube, serve to yieldingly support the tube in its normal position. When the aspirating or jet tube 71 is in this position. the intake end thereof occupies a predetermined position below the fuel level 24 in the well 626;.

During idling of the engine, the suction thereof will cause the fuel to enter the aspirating or jet tube 71 by way of its lower end and will cause air to enter the tube by way of the port 75, the air and fuel discharging from the upper end of the tube into the mixing chamber 621), and thereafter passing to the engine by way of the opening 70.

When the engine is idling, the slow speed of the suction thereof will not be sufficient to cause the air acting against the under side of the piston 7 3 to lift the aspirating or jet tube 71, and while the engine is idling at rapid speed, the suction will be sufiicient to permit the air acting against the piston to lift the tube. It will thus be seen that in slow idling of the engine, the intake end of the aspirating or jet tube 71 will occupy its maximum position below the fuel level 24:, and that during fast idling of the engine, the intake end of the tube will be in a higher position with respect to the fuel level, with the result that the mixture will be held to the same proportions at all idling speeds. Means are provided for limiting the extent of the upward movement of the aspirating or jet tube 71 during rapid idling speed, and this means comprises a coil spring 78 bearing against the piston 73 and a washer 7 9 carried by a screw 80, the screw being readily engaged with the upper chamber closure 64 to permit the tension of the spring to be varied. The effective size of the opening is varied by slightly cracking the throttle valve 40 through the medium of a set screw 70a car'- ried by the body 1 and contacting with the arm 42.

WVhile I have described the principle of the invention, together with the structure which I now consider the preferred embodiment thereof, it is to be understood that the structure shown is merely illustrative and that such changes may be made, when desired, as fall, within the scope of the invention as claimed.

1. A carburetor for an internal combustion engine, comprising a fuel well, a nozzle occupying a fixed position above the level of the fuel, slidably mounted tube having its intake end immersed in the fuel and its discharge end positioned in the nozzle, and means for moving the tube to vary the height of its intake end with respect to the fuel level.

2. A carburetor for an internal combustien engine, comprising a fuel well, a nozzle occupying a fixed position above the level of the fuel, slidably mounted tube having its intake end immersed in the fuel and its discharge end positioned in the nozzle, and means for moving the tube to lower its discharge end with respect to the fuel level on a decrease in the engine suction and to raise the discharge end with respect to the fuel level on an increase in engine suction.

3. A carburetor for an internal combustion engine, comprising a fuel well, a vertically sliding aspirating tube having its in take end immersed inthe fuel and its discharge end open to engine suction and arranged above the fuel level, a throttle valve, and means connecting the tube to the throttle valve to cause the tube to be lowered with respect to the fuel level by the throttle valve as the latter is closed and to cause the tube to be raised with respect to the fuel level by the throttle valve as the latter is opened.

4. A carburetor for an internal combustion engine, comprising a fuel well, a slidable aspirating or jet tube having its intake end immersed in the fuel and its discharge end open to engine suction and arranged above the fuel level, a throttle valve, a crank connected to the throttle valve, a slidably mounted rod connected to the tube, a link pivotally connected to the rod, means carried by the crank for adjusting the link about its pivot, and means establishing a yielding connection between the link and crank, said crank, rod, link and means connecting the tube to the throttle valve for upward movement by the throttle valve during the opening of thevalve and for downward movement by the throttle valve during the closing of the valve.

5. A carburetor for an internal combustion engine, comprising a fuel well, a vertically sliding aspirating tube having its intake end immersed in the fuel, and its discharge end open to engine suction and arranged above the during the opening of the valve and to cause the tube to be lowered with respect to the fuel level by the throttle valve during the closing of the valve, the adjustability of the means; permitting the extent of the movement of the tube by the throttle valve to be varied.

6. A carburetor for an internal combustion engine, comprising a fuel well, a vertically sliding aspirating or jet tube having its intake end immersed in the fuel and its discharge end open to engine suction and arranged above the fuel level, a throttle valve, and adjustable means connecting the tube to the throttle valve to cause the tube to be raised with respect to the fuel level by the throttlevalve during the opening of the valve and to cause the tube to be lowered with respect to the fuellevel by the throttle valve during the;

closing ofthe valve, the adjustability of the means permitting the tube to be adjusted upwardly or downwardly with respect to the valve.

7. A carburetor for an internal combustion engine, comprising a fuel well, vertically sliding aspirating or jet tube having its'intake end immersed in the fuel and its discharge end, open "to engine suction and arranged above the fuel level, a throttle valve, and adjustable means connecting the tube to the throttle valve to cause the tube to be raised with respect to the fuel level by the throttle valve during the opening of the valve and to cause the tube to be lowered with respect to the fuel level by the throttle valve during the closing of the valve, the adjustability of the means permitting the tube to be adjusted vertically with respect to the valve and permitting the extent of the adjustment of the tube by the valve to be varied.

8. A carburetor for an internal combustion engine, comprising a fuel well open at its upper end to the atmosphere, a nozzle occupying a fixed position above the level of the fuel, a -vertically sliding aspirating or jet tube having its intake end immersed in the fuel and its discharge end positioned above the nozzle, means for adjusting the tube to vary the height of its intake end with respect to the fuel level as the engine suction varies, the tube being provided adjacent its discharge end with air inlet ports and having its passage restricted below said ports, a acket for directing air to said ports and cutting them oil from communication with the fuel in the well, and

, a combining tube fixed to the upper end of the aspirating or jet tube and extending therefrom to the nozzle.

9. A carburetor for an internal combustion engine, comprising a fuel well open at its upper end to the atmosphere, an adjustable aspirating or jet tube having its intake end immersed in the fuel and its discharge end. open to engine suction and arranged above the. fuel level, means for adjusting the tube to vary the height of its intakeend with respect to the fuel level as the engine suction varies, the tube being provided adjacent its I discharge'end with air inlet ports and hav-' ing its passage restricted below said ports, a

combining tube surrounding theup er end of the aspirating or jet tube above said ports and provided in its lower end with air inlet ports, and a j acketsurrounding the adjacent parts of said tubes and adapted to supply air to said ports, and cut-off communicationbetween said ports and the fuel.

10. A carburetor for an internal combustion engine, comprising a Venturi choke, a fuel well located below the choke, aguide tube arranged in and spaced from the walls of* the choke, an adjustable aspirating or jet tube having its intake end immersed in the fuel and its discharge end open to engine suction and arranged above the fuel level, the aspirat ing or jet tube being provided below' its dis-: charge end with air intake ports and having its passage restricted below said ports,'a combining tube having its lower end secured to and surrounding the upper end of the aspirat f ing or jet tube and havingits upper end anranged in the guide tube,.the combiningtube being provided in its lower end with air intake ports, a jacket surrounding the ad- 1 j acent parts of the aspirating or j et tube and i combining tube end shutting off communication between the ports of these tubes and they fuel, thejacket extending above the fuel well and provided near its upper end with air in take ports, and means for adjusting the aspirating or jet tube to vary the height of its intake end with respect to the fuel level as the engine suction varies.

11. A carburetor for an internalcombustion engine, comprising a Venturi choke, a'-

fuel well located below the choke, a guide tube arranged'in and spaced from the walls of the choke, an adjustable aspirating or jet tube having its intake end immersed in the fuel and its discharge end open to engine suction and arranged above the fuel level, the aspirat ing'or jet tube being provided below its dis-f charge end with air in'take ports and having its passage restricted below said ports, a combining tube having its lower end securedto' and surrounding the upper end of the aspirato ing or jet tube andhaving its upper end arranged in the guide tube, the combining tube' being provided in'its lowerend with air intake ports, a jacket surrounding the adjacent parts of the'aspirating or jet tube and combining tube and shutting off. communicationbetween the portsof these tubes and the fuel..

the jacket extending-above the fuel well and provided near its upper end with air intake ports, a throttle valve arranged'abovethe choke, and means connecting the aspirating and combining tubes to the throttle valve to permit them to be adjusted to increase the height of the discharge end of t'he'jet tube withrespect to the fuel level as the throttle valve closes and to increase its height with respect to the fuel level as the throttle valve opens.

12. A carburetor for an internal combustion engine, comprising a throttle valve, a chamber having a lower fuel compartment and an upper air compartment, the fuel compartment being open at its upper end to the atmosphere and the air compartment being open at its lower end to the atmosphere and communicating at its upper end with the interior of the carburetor at a point above the closed position of the throttle valve, an idling aspirating or jet tube slidably mounted in the chamber with its lower end immersed in the fuel and its upper end located close to the point of communication between the air compartment and the interior of the carburetor, the tube being provided therein with ports communicating with the air compartment,

and a piston fixed to the tube and arranged in the air compartment and subject to engine suction to permit the tube to be raised as the idling speed of the engine increases so as to maintain the proportions of the fuel mixture discharging from the tube.

13. A carburetor for an internal combustion engine, comprising a throttle valve, a chamber having a lower fuel compartment and an upper air compartment, the fuel compartment being open at its upper end to the atmosphere and the air compartment being open at its lower end to the atmosphere and communicating at its upper end with the interior of the carburetor at a point above the closed position of the throttle valve, an idling aspirating or jet tube slidablv mounted in the chamber with its lower end immersed in the fuel and its upper end located close to the point of communication between the air com- ,partmentand the interior of the carburetor, the tube being provided therein with ports communicating with the air compartment. a piston fixed to the tube and arranged in the air compartment and subject to engine suction to permit the tube to be raised as the idling speed of the engine increases so as to maintain the proportions of the fuel mixture discharging from the tube, means for yieldingly supporting the tube is normal position,

and adjustable means for yieldingly resisting the upward movement of the tube.

14. A carburetor for: an internal combustion engme,compr1s1ng a throttle valve, a

chamber having a lower fuel compartment and an upper air compartment, the fuel eom-.

partment being open at its upper end to the atmosphere and the air compartment being open at its lower end to the atmosphere and communicating at its upper end with interior of the carburetor at a point above the closed position of the throttle valve, an idling aspirating or jet tube slidably mounted in the chamber with its lower end immersed in the fuel and its upper end located close to the point of communication between the air compartment and the interior of the carburetor, thetube being provided therein with ports communicating with the air compartment, and a piston fixed to the tube and arranged in the air compartment and subject to engine suction to permit the tube to be raised as the idling speed of the engine increases so as to maintain the proportions of the fuel mixture discharging from the tube, the tube having its passage restricted below its air inlet ports.

15. A carburetor for an internal combustion engine, comprising a fuel well, a venturi, a nozzle having a fixed position within the venturi, a slidably mounted tube having its intake end immersed in the fuel and its discharged end positioned in the nozzle, and means for moving the tube to vary the height of its intake end with respect to the fuel level.

16. A carburetor for an internal combustion engine, comprising a fuel well, a venturi, a nozzle having a. fixed position within the venturi and extending above and below the throat thereof, a slida-bly mounted tube having'its intake end immersed in the fuel and its discharge end positioned in the nozzle, and

means for moving the tube to vary the height signature.

NATHAN E. GASTON 

